The first chemotherapy cycle that Armstrong underwent included BEP, but for the three remaining cycles, he was given an alternative, vinblastine etoposide, ifosfamide, and cisplatin (VIP), to avoid lung toxicity associated with bleomycin. Shortly afterward he was told that his contract with the Cofidis team had been cancelled.

Armstrong's total points in 1987 as an amateur were better than those of five professionals ranked higher than he was that year.

In 1993, Armstrong won 10 one-day events and stage races, but his breakthrough victory was the World Road Race Championship held in Norway.

Before his World Championships win, he took his first win at the Tour de France, in the stage from Châlons-sur-Marne to Verdun.

Armstrong retired from racing at the end of the 2005 Tour de France, but returned to competitive cycling with the Astana team in January 2009, finishing third in the 2009 Tour de France later that year.

Between 20, he raced with Team Radio Shack, the UCI Pro Team he helped found. Armstrong had been the subject of doping allegations ever since winning the 1999 Tour de France.

In 2012, a United States Anti-Doping Agency investigation concluded that Armstrong had used performance-enhancing drugs over the course of his career As a result, he received a lifetime ban from all sports that follow the World Anti-Doping Code—effectively ending his competitive career.